Researching in the Spiral Archive turns out to be tricky, and much more physical than Vershab expected. The stone stairs only allow access to a small portion of the circular shelves, forcing the researchers to venture the flimsy-looking papyrus bridges to find what they're looking for. Cautious testing proves that the bridges are as strong as thick leather, but also flexible, bowing when weight is placed on them.

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In other words, every Research check attempted in the Spiral Archive requires an Acrobatics check to safely cross the bridges. It is also possible avoid having to attempt an Acrobatics checks by slowly and carefully moving across the bridges, but that wastes a lot of time, and the character takes a –2 penalty on his Research checks for that day.